174 



ELEMENTS OF GENERAL SCIENCE 



they have been relatively unimportant because their work has 

 not been of a useful kind (fig. 88). 



Of late years men have taken part of the water from the 

 river above the Falls and caused it to flow through turbine 

 water wheels on its way to the lower level in the gorge. This 

 part of the water therefore turns the wheels and the dynamos 



FIG. 88, Work done by Niagara Falls 



At Niagara the river falls into the head of a narrow, steep-walled gorge. The 

 gorge has been made by the river 



connected with them instead of wearing away the rock of 

 the Falls. Thus the Falls have been harnessed and com- 

 pelled to do useful work. The beauty and impressiveness of 

 Niagara Falls are so great that the Falls are probably worth 

 more to us in their natural state than the energy we could 

 derive from them would be worth, but there are many other 

 places where water power can be produced without destroy- 

 ing great scenic beauty. It is necessary to take advantage 



